Lesson 2 - 3

1. Lesson 2 - 3 Additional Displays of Quantitative Data

2. Objectives • Construct frequency polygons • Create cumulative frequency and relative frequency tables • Construct frequency and relative frequency ogives • Draw time-series graphs

3. Vocabulary • Class midpoint – adding consecutive lower class limits and dividing by 2 • Frequency polygon – Plot a point above each class midpoint on a horizontal axis at a height equal to the frequency of the class. After points are plotted, straight lines (line-plot) are drawn between consecutive points • Cumulative Frequency Distribution – displays the aggregate frequency of the category • Cumulative Relative Frequency Distribution – displays the proportion (or percentage) of observations less than or equal to the category for discrete data and less then or equal to the upper class limit for continuous data • Ogive – a line-plot graph that represents the cumulative frequency or cumulative relative frequency for the class • Time-Series Plot – plots (line-plots) time along the horizontal access and the corresponding variable value along the vertical axis

4. Summary and Homework • Summary • Homework: • pg 101 - 104: 8, 11, 19